How is the HLB value range of non-ionic demulsifiers determined?
The HLB value range of non-ionic demulsifier product is mainly determined by the following several methods:
1.Theoretical calculation to determine the HLB value of demulsifier product It can be estimated based on the chemical structure of non-ionic demulsifier product. For example, the HLB value can be roughly determined by calculating the relative content of hydrophilic and lipophilic groups in the molecule of demulsifier product.
Common calculation formulas such as Griffin's method: HLB = 20 × (molar mass of hydrophilic part / molar mass of surfactant). However, the result obtained by this calculation method is only an approximation and not necessarily very accurate.
2.Experimental Measurement to determine the HLB value of demulsifier for oilfield
1).Emulsification experiment to determine the HLB value of demulsifier for oilfield : Different HLB values of non-ionic demulsifier additive for crude oil are mixed with a specific oil-water system respectively and their emulsification and demulsification effects are observed.
Gradually adjust the composition or structure of the demulsifier additive for crude oil to find the HLB value range corresponding to the best demulsification effect. Through a large number of experiments on different oil and water samples, the approximate HLB value range of non-ionic demulsifier additive for crude oil suitable for different types of oil-water systems can be summarized.
2). Cloud point method to determine the HLB value of demulsifier for oilfield : For some non-ionic demulsifier additive for crude oil, their solubility in aqueous solution changes with temperature. When the temperature rises to a certain extent, the solution will become turbid. This temperature point is called the cloud point. The cloud point has a certain relationship with the HLB value of the demulsifier dewatering and the HLB value range can be indirectly determined by measuring the cloud point.
3).Phase transition temperature method to determine the HLB value of demulsifier for oilfield : In a specific oil-water system with the change of temperature, non-ionic demulsifier dewatering may cause the system to change from water-in-oil type to oil-in-water type or vice versa. This phase transition temperature is related to the HLB value of the demulsifier dewatering and the HLB value range can be determined by measuring the phase transition temperature.
3. Experience Summary Through long-term practice and research, a large amount of empirical data on non-ionic demulsifier dewatering in different application scenarios has been accumulated in the industry. Based on these experiences, the effective HLB value range of different types of non-ionic demulsifier product in specific oil-water systems can be roughly determined. For example, for some specific crude oil emulsions, after a large number of practical applications and experimental verifications, more appropriate HLB value ranges of some commonly used non-ionic demulsifier additive have been determined.
